I build my hoods too. This is the one over my 135 gallon viv. Its built out of 1/2 sanded plywood and pine. It sets on the to of the tank and bolts to the plastic lip. Everything is organized into layers: screen, then 6 T-12 40 Watt bulbs, a layer of MDF coated with aluminium foil tape, above all that are the vent and circulation fans and the plumbing for an irrigation system I never finished. It is hinged in the back with a 72in piano hing. It works well, but it is kind of heavy to lift. All the balast and controls are in the stand below.
The tank doesn't look the same anymore, but the stand and hood do. So here they are: